Grease pumping apparatus



Jam. 9, 1934.

J. w. WOODRUFF- GREASE PUMPING APPARATUS 3 Sheets-Sheet l Filed Dec. 12, 1930 ATTGRNEYS `Fan. 9, ,1934.

J. W. WOODRUFF GREASE PUMPING `APPARATUS Filed Dec. l2, 1930 3 Sheets-Sheet 3 Patented Jan. 9, 1934 UNITED STATES PATENT OFFICE Application December 12, 1930 Serial No. 501,752

2 Claims. (Cl. 10S-42) This invention relates in general to pumps and more particularly to a pump for handling heavy grease, one object of the invention being to provide a novel and improved easily portable pumping apparatus wherewith grease can be withdrawn directly from a container, such as a drum and forcedfrom the apparatus at a high pressure, for example, three or four thousand pounds per square "nch, to any desired point, for example, a vehicle spring bearing from which it is desired to force dirt and old grease simultaneously with and by the injection of new grease.

Another object is to provide pumping apparatus of this character including a single cylinder having two pumping chambers, one an intake chamber and the other an outlet chamber, and va valved piston common-to both chambers for drawing grease from a container or the like into the intake chamber and ejecting the grease from the outlet chamber, said intake and outlet chambers and the effective areas of the respective ends of said p'ston being of such relative proportions that a volume of grease is drawn into the intake chamber in excess of the volume of the outlet chamber, whereby complete charging of the outlet chamber is ensured and the possibility'of air entering the outlet chamber and becoming mixed with the grease is obviated.

A further object is to provide in such a pumping apparatus novel and improved means whereby the excess volume of the grease drawn into the intake chamber upon one stroke of the piston can be ejected from the intake chamber on the opposite stroke of the piston so as not to interfere m5 with the operation of the piston. A

Another object is to provide a pumping apparatus of the character described embodying novel and improved means for increasing the pressure of the grease in the outlet chamber far above the pressure of the grease in the intake chamber; for example, the pressure in the intake chamber may be a few hundred pounds, while the pressure in the outlet chamber may be three or four thousand pounds.

Still another object of the invention is to provide such a grease pumping apparatus wherein the effective area of the end of the piston cooperating with the intake chamber is many times greater than the effective area of the end of the piston cooperating with the outlet chamber, the piston having a valve which will permit grease to be drawn into the intake chamber on one stroke of the piston and allow the grease to pass from the intake chamber to the outlet chamber on the opposite stroke, so that the grease in the outlet chamber is ejected therefrom upon the next stroke at a greatly increased pressure. In other words, grease is drawn into the intake chamber on one stroke, and a previous charge of grease is ejected from the outlet chamber on the 6o same stroke at a much higher pressure.

Other objects are to provide a novel and improved inlet valve for the intake chamber of the pump; to combine with such an inlet valve a relief valve for permitting the excess volume of grease in the intake chamber to be ejected from the intake chamber; to provide such a valve construction whereby foreign matter may` be forced from the inlet end of the pump cylinder as the excess volume of grease is ejected from the intake chamber so as to prevent clogging of the pump cylinder inlet; and to obtain other advantages and results as will be brought out by the following description.

Referring to the accompanying drawings in which corresponding and like parts are designated throughout the several views by the same reference characters,

Figure l is a side elevation of the pumping apparatus embodying my invention with the pump so cylinder shown in ,vertical section.` n

Figure 2 is an enlarged vertical sectional View through the pump cylinder, piston and valves.

Figure 3 is a similar and complemental view of the motor and valve mechanism.

Figure 4 is a fragmentary vertical sectional view through the lower end of the pump cylinder showing the parts during the up-,stroke of the pump piston.

Figure 5 is a similar view showing the parts 9o during the down-stroke of the pump piston.

Figure 6 is a horizontal sectional view on the line 6 6 of Figure 2.

Figure 7 is a similar view on the line 7--7 of Figure 2.

Figure 8 is an enlarged side elevation of the pumping apparatus showing the valve mechanism and the actuating means therefor in detail, the valve mechanism being shown in the position to admit uid pressure to the upper end of the mo- 100 tor cylinder to actuate the pump piston on its down-stroke.

Figure 9 is a similar view showing the valve mechanism at the intermediate position, and y Figure 10 is a like view showing the valve mech- 105 anism and actuating means therefor in the position to admit uid pressure to the lower end of the motor cylinder for actuating the pump piston on its up-stroke.

Specifically describing the illustrated embodiment of the invention, the pumping apparatus includes a pump cylinder A of a length to be inserted into a drum or other container for grease or the like, said cylinder having an inlet end 1 to rest upon the bottom of a drum or container, and having thereon a screen 2 for preventing large solid particles from entering the pump cylinder. Within the inlet end l of the cylinder is a combined intake and relief valve B for admitting grease into the lower or intake chamber C of the pump cylinder which is located at one side of a piston D at the other side of which the pump cylinder has an outlet chamber E at the upper end of which is an outlet opening EE controlled by an outwardly opening check valve mechanism F of any suitable construction. The piston D is reciprocated in the pump cylinder A by a fluid pressure motor G including a cylinder H mounted upon the upper end of the pump cylinder A, and a piston I reciprocable in said cylinder H and connected by a piston rod K to the pump piston D.

Operation of the motor G is controlled by a valve mechanism and operating means therefor, generally designated L, which is automatically operated by the rod M connected to the motor piston I and projecting outwardly from the motor cylinder, so that the pump piston D is automatically and continuously reciprocated in the pump cylinder so long as fluid pressure is applied to the motor. i

More specifically describing the invention, the intake and relief valve B comprises a hollow cylindrical body 3 reciprocable in the intake end of the pump cylinder, and having at one end a head 4 to cooperate with an inwardly facing valve seat 5. Between the head 4 and lche body 3 of the valve is a reduced neck portion 6 which provides an annular chamber 'l between the valve and the pump cylinder, and the body 3 of the valve is provided with openings 8 leading into said annular chamber. The valve head 4 is normally influenced against the seat 5 by a compression spring 9.

The head of the valve is provided with a substantially coaxial port or passage 10 which leads from the interior of the body 3 of the valve through the head into the intake chamber C of the pump cylinder. At the end of said passage opposite the intake chamber C is an outwardly facing valve seat 11 with which cooperates a relief valve l2 normally held against its seat by a spring 13, and closed upon infiowing of grease into the intake chamber C.

Preferably the valve B is an entity and is shown as comprising a casing 14 screw-threaded into the pump cylinder A at 15 and having the valve body 3 reciprocable therein and the valve seat 5 at one end thereof, With this construction the valve B can be easily removed from the pump cylinder for repair or replacement.

The pump piston D comprises a cylindrical block 16 to nicely slide in the pump cylinder, and has an axial passage 17 therethrough controlled by a ball check valve 18 cooperating with an upwardly facing seat 19. This valve is arranged to close on the up-stroke of the piston and open on the down-stroke. A packing ring 20'is secured to the upper end of the block 16, and the block is connected by the piston rod .K to the motor piston I. This piston rod K is shown as comprising a tubular section 21 having lateral openings 22 for permitting the flow of grease from the passage 17 in the piston block 16 into the outlet chamber E. This section 21 is connected t0 a solid section 23 which has a screw threaded connection 24 with the motor piston I, and passes through a gland 230 between the pump cylinder and the motor cylinder.

The diameter of the section 23 is somewhat less than the diameter of the piston D, and the section 23 always projects into the outlet chamber E, which in effect causes the end of the piston D facing the outlet chamber to have an effective area equal to the area of the annular space between the circumference of the section 23 and the inner walls of the outlet cylinder E. This area is considerably less than the area of the end of the piston D facing the intake chamber C, and both of these areas are much less than the area of the motor piston I, as clearly shown on the drawings. For example, the effective area of the motor piston may be approximately 15 square inches, while the area of the space between the section 23 of the piston rod K and the walls of the outlet chamber may be approximately Ag (.56) of a square inch, and the area of the end of the piston D in the intake chamber may be approximately 1% (1.75) square inches. Obviously, this will result in the grease being pumped at different pressures in the intake chamber C and the outlet chamber E and these pressures will be relatively greater than the pressure of fluid required to operate the motor piston I. In other words, the motor piston I may be actuated by fluid pressure at, for example, a hundred pounds per square inch and the grease may be ejected from the outlet chamber E at a pressure of several thousand pounds per square inch. Therefore, great economy in power is achieved, and the parts of the apparatus are extremely small in relation to the extremely high pressures produced thereby.

Also, the intake chamber C has a working ,capacity or volume several times greater than the working capacity or volume of the outlet chamber between the limits of the stroke of the piston, so that a volume of grease in excess of said working capacity of the outlet chamber E will be drawn into the intake chamber upon each intake-stroke of the piston D, so as ensure that the outlet chamber E will be completely charged with grease and to prevent air bubbles from forming and ensure a uniform discharge of grease from the outlet.

The operation of the pump piston will be understood from the foregoingrbut will be generally described. Assuming the pump to be empty, the pump cylinder A is inserted into a container of grease, and the power turned on to the motor G. On the up-stroke of the piston D the intake valve B is opened as shown in Figure 4 of the drawings, while the piston valve 18 is closed. Grease is thus drawn in through the intake valve B into the intake chamber C. On the downstroke of the pump piston D, the valve B closes while the piston valve 18 opens, as shown in Figure 5 of the drawings, so that the grease is forced from the intake chamber into the outlet chamber E. This continues until the outlet chamber is completely filled, the excess of grease in the inlet chamber over what is necessary to ll the outlet chamber to its workingcapacity ensuring that there shall be plenty of grease in the inlet chamber to ll the outletchamber and prevent accumulation of air bubbles therein, even if the piston does not efhciently draw the grease into the inlet chamber so as to ll it. The remaining excess volume of grease lwill be ejected through the relief valve 12 which opens as shown in Figure 5, and air bubbles in the grease will also be released through said relief valve. Obviously, the tension of spring 13 will be adjusted to prevent opening of the relief valve until the outlet chamber has been fully charged. In other Words, the spring will be adjusted to open when the pressure in the outlet chamber and inlet chamber reaches a certain point at which the outlet chamber normally will be fully charged. It will be noted that this ejected excess grease will tend to clean the inlet end of the pump cylinder and the screen 2 so as to remove particles of foreign matter therefrom and prevent clogging thereof, and cannot impede movement of the pump piston.

On the next up-stroke of the pump piston B,

another charge of grease is drawn into the intake chamber, while the previous charge of grease in the outlet chamber is forced outwardly through the outlet opening and check valve F at a high pressure. This operation of the pump willV then continue with one charge of grease being ejected simultaneously with the intake of a new charge.

It will be nderstood by those skilled in the art that the various proportions or ratios of areas of the variouspiston surfaces, as well as the length of stroke of the pistons may be widely modified and changed according to requirements without departing from the spirit or scope of the invention. Also, it will be understood thatthe piston rod K might be made in one piece of the same diameter as the section 23, with a portion of the rod cored out or provided with a passage corresponding to the passage of the section 21, communicating with the port 17 through the piston block 16.

As above described, the motor G includes the cylinder H which has the respective heads and 26, and each head has a lateral lug 27 to which is secured a valve for controlling the flow of fluid under pressure to and from the corresponding end of the cylinder. identical in construction, and accordingly only one will. be described in detail. Each valve includes a casing 30.1ha-ving a flange 31 secured as by screws 32 tothe corresponding lug 27 onthe head of the cylinder. This casing also has a port 310 registering with`a duct 320 leading through the head of the cylinder into the corresponding end of the cylinder. The casing is essentially cylindrical in shape and is disposed with its axis approximately parallel to the axis of the motor cylinder, and the valves are reversely arranged. At one end of the valve casing is an inlet connection 33 to which is connected a fluid pressure supply pipe 34. The inlet is controlled by a ball valve 35 which closes in the direction of the incoming fluid pressure and under influence of a spring 36. This valve lcontrols a port 37 which communicates through the interior of the valve casing with the port 31. Through the port 37 is loosely slidable a tubular valve stem 38 which is also slidably mounted in an opening 39 in the casing and projects beyond the casing. The opening through this tubular stem has lateral passages 40 venting to the atmosphere. Ihe inner end of the valve stem is adapted to engage the ball 35 so that when the stem is pushed inwardly of the casing the ball is unseated and permits fluid under pressure to flow into the corresponding end of the motor cylinder. Upon release of the valve stem 38, the stem is pushed outwardly of the casing as the ball 35 is seated and the pressure in the motor cylinder raises the valve stem These valves 28 and 29 arey from the ball so that the air in the motor cylinder is lpermitted to vent through the valve stemto' the atmosphere. In this connection it should be noted that the valve stem has a shoulder 41 facing into the valve casing which serves as a piston to receive the pressure of the fluid and raise the valve stem from the ball.

To operate the motor G, one valve must be opened to supply fluid to one end of the motor cylinder and the other valve must be simultaneously closed and permitted to vent the fluid from the other end of the motor cylinder. As

above stated, thevalves are reversed so that the outer ends of the stems are adjacent each other and in opposed coaxial relation as clearly shown in the drawings. Between these stems and extending laterally is an operating lever 42' which has a pin and slot connection 43 at one end with a fixed bracket 44 substantially half-way between the outer ends of the valve stems. The other end of the lever is preferaby in the form of a loop 45 through which passes a rod 46 having a gooseneck 47 between its ends and swivel connected at one end as at 48 to the piston rod M of the motor piston I. Upon the rod 46 are a pair of spaced collars 49 and 50. These collars are so spaced that as the motor piston I approaches the limits of each stroke, one collar engages the lever to swing the same in one direction. In other words, when the motor piston is moving downwardly and reaches its lower limit, the collar 50 engages the lever 42 and pushes it downwardly as shown in Figure 10 of the drawings, while atthe limit of the upward stroke of the motor piston, the collar 49 engages the lever and raises the same as shown in Figure 8 of the drawings. As the lever 42 is pushed downwardly its intermediate portion engages the valve stem 38 of the valve 28 so as to open the valve and permit fluid under pressure to flow into the lower end of the motor cylinder which starts the motor cylinder on its upward stroke. At this time the lever is moved away vfrom the valve stem ofthe valve 29 so that the fluid in the upper end of the motor cylyinder is vented to the atmosphere. When the motor piston reaches the end of its upper stroke, the valve stern of the vave 29 is actuated to open the valve 29 and permit fluid under pressure to flow into the upper end of the cylinder; and simultaneously the lower` valve 28 is opened to vent the fluid fromits ends of the cylinder.

For holding the valve stems of the valves 28 and 29 in valve opening position, I provide a roller 51 on the lever 42 which cooperates with a triangular detent head 52 ona detent lever 53 pivoted at one end as at 54 upon the lower valve casing. The other end of the detent lever is influenced by a spring 55 to move the detent head 52 into the path of the roller 5l. In the movement of the lever 42 from one position to the other, the roller 51 pushes the detent head 52 out of its path, and after the roller 5l has passed the detent head, the detent lever 53 is snapped over the roller 51 by the spring 55, whereby the detent head 52 holds the lever 42 in both of its valve opening positions, as clearly shown in Figures 8 and 10. At the end of'each stroke of the motor piston, the pin 43 is at one end of the slot. As the lever approaches its intermediate position as shown in Figure 9, the

pin of the pin and slot connection moves in the slot to the other end of the slot under the inuence of the corresponding collar 49 or 50 and the detent head 52 upon the lever, so that the lever is snapped from the intermediate position into the valve opening position toward which it was being moved, and ensures an opening of each valve 28 and 29 with a snap action to admit fluid into the corresponding end of the motor cylinder slightly before the motor piston reaches the limit of its stroke. Similarly, the valve stem is released with a snap action to vent fluid from the corresponding end of the motor cylinder before the motor piston starts on its opposite stroke. The movement of the lever at the pin and slot connection causes the lever to hold the valve open long enough to ensure movement of the piston rod sufficiently to cause the roller 51 to pass the detent head, ensuring against the lever hanging or stopping at its intermediate position, and permitting acceleration of the movement of the lever by the detent lever.

From the foregoing it will be understood that as soon as the fluid under pressure is supplied through the pipe 34, operation of the motor G will start, and this operation will automatically continue so long as the power is applied or until the pressure built up in the outlet of 'the pump is great enough to resist the pressure actuating the motor piston. This is an important advantageof my invention, since where the outlet of the pump is connected to a distributing hose having an outlet valve at its end, the operator automatically controls operation of the pump by a simple opening and closing of the control valve at the end of the hose. The grease may be withdrawn from a drum or other container at substantially atmospheric pressure upon one stroke of the piston D, and during the same stroke, grease may be ejected from the outlet chamber E at a pressure of several: thousand pounds. The operation of the apparatus is quick and positive, and the whole apparatus constitutes a single unit which can be easily transported from place to place for usel While I have shown and described the -invention as embodied in certain details of construction, it should be understood that this is primarily for illustrating the principles of the invention and that many modifications and changes may be made in the details of construction of the apparatus without departing from the spirit or scope of the invention.

Having thus described my invention, what I claim is:

1. Pumping apparatus for heavy viscous material comprising a cylinder, a valved piston reciprocable therein intermediate its ends and forming an inlet chamber at one end and an outlet chamber at the `other end, said outlet chamber having a discharge opening and an outlet check-valve therein, means for reciprocating said piston, a check-valve controlled inlet for said inlet chamber, so that on each upward stroke of said piston the material being pumped is drawn into said inlet chamber, on the downward stroke a portion of the material in the inlet chamber is forced into said outlet chamber, and on the next upward stroke said material in the outlet chamber is ejected through said discharge opening, said inlet chamber having a maximum working capacity several times greater than said outlet chamber so as to receive a quantity of material in excess of the maximum working capacity of the outlet chamber between the limits of stroke of the piston, and the ends of said piston in the inlet chamber having an effective area several times greater than the end of the piston in said outlet chamber so as to draw material at low pressure into said inlet chamber in excess of the amount required to ll said outlet chamber to its maximum working capacity and to eject the material from said outlet chamber at a substantially higher pressurerespectively, and a relief valve for releasing the excess material from said inlet chamber when said outlet chamber is completely illled.

2. Pumping apparatus for heavy viscous material comprising a cylinder, a valved piston reciprocable therein intermediate its ends and forming an inlet chamber at one end and an outlet chamber at the other, said chambers being of the same diameter and said outlet chamber having a discharge opening, a piston rod connected to said piston and passing through said outlet chamber and of a diameter to reduce the effective area of said piston in the outlet chamber to substantially less than the effective area of said piston in the inlet chamber and so that said inlet chamber has a several times greater maximum working capacity than said outlet chamber between the limits of stroke of said piston, a check-valve controlled inlet for said inlet chamber, an outlet check-valve in said discharge opening, and means connected to said piston rod outside said cylinder for reciprocating the piston, so that on each upward stroke of the piston the material being pumped is drawn intol said inlet chamber at low pressure in an amount in excess of the maximum working capacity of the outlet chamber, on the downward stroke the material is forced into the outlet chamber so as to completely Iill the latter toits maximum Working capacity, and on the next upward stroke said material in the outlet chamber is ejected through said discharge opening at higher pressure, and a relief valve for releasing the excess material from said inlet chamber through said inlet when said outlet chamber is completely filled, said excess material serving tc remove particles of foreign matter from said inlet and to agitate the material adjacent the inlet to make it more easily flow inwardly through the inlet.

JOSEPH w. WOODRUFF. 

